A rep for Mick Jagger tells FOX411 the Rolling Stones frontman is "shocked and devastated" by the news that longtime girlfriend and fashion designer L'Wren Scott was found dead of an apparent suicide Monday morning.

“A female 49 years of age was found unconscious and unresponsive” in an apartment that shares Scott's address, an NYPD spokesperson told FOX411.

An official close to the investigation said Scott's assistant found her hanging from a doorknob. The official said no note was found, and there was no sign of foul play.

The NYPD told us the body was found at approximately 10 a.m. and that “it does appear to be an apparent suicide, preliminarily.”

The spokesperson said the identity of the female would not be officially confirmed until the family had been notified.

Scott was a fashion designer to celebrities including First Lady Michelle Obama, Nicole Kidman, Amy Adams and Penélope Cruz. The Utah-native, who grew to be 6-foot-3, first began designing clothing for her tall figure during her teenage years. Through the years, she worked closely with some of the top names in fashion, including cosmetics mogul Bobbi Brown.

"I am devastated by the tragic news about L’Wren. She was a visionary designer who I very much enjoyed working with, but she was also smart and kind," Brown stated. "My thoughts and heartfelt condolences go out to her loved ones during this very sad time."

Scott canceled her London Fashion Week show this winter due to reported production delays.

She and Jagger began dating in 2001. Jagger is currently touring with his band in Australia, according to his most recent tweet. The rocker wrote, "Great to be back In Australia! Looking forward to the first show in Perth." That tweet has since been deleted.